Resolving the Shortcomings in Modern NH3 Kinetics Models using Detailed Species Time Histories and Direct Rate Measurements

使用详细的物种时间历史和直接速率测量解决现代 NH3 动力学模型的缺点

• 批准号: 2308433
• 负责人: Eric Petersen
• 金额: $ 41万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-15 至 2026-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2308433&HistoricalAwards=false
• 关键词: Resolving; Shortcomings; Modern; NH3; Kinetics

Because of its zero-carbon content and established production methods, ammonia (NH3) has drawn much interest as a fuel for power generation and propulsion. Many research studies worldwide have been conducted over the past few years in an attempt to understand and predict its combustion chemistry. However, there are wide discrepancies among current models that are used to predict the combustion behavior of ammonia, and none can match the entire existing data set, so progress has been incremental and sometimes inconsistent. This project will resolve much of the current discrepancies and increase the reliability and predictive capability of ammonia chemistry models. The PI and his team will utilize state-of-the-art laser diagnostics and lab facilities to measure the model parameters that are currently missing. Research into hydrogen-based fuel sources such as ammonia will ultimately help to reduce the production of greenhouse gases globally. This multidisciplinary research project will allow graduate students from both mechanical engineering and physical chemistry backgrounds to interact on a daily basis. Ongoing, complementary projects in the PI’s lab and the Turbomachinery Laboratory’s undergraduate research program will broaden the number of participants while giving undergraduate students exposure to research using lasers for combustion chemistry.Although many results have been generated in recent years on ammonia chemical kinetics, most of the data have been for characterization of global reactivity, namely ignition delay times and laminar flame speeds. However, improved insight into the chemical kinetics of NH3 can be made by focusing on the measurement of detailed species time histories in a shock tube. Such measurements can be tailored for the validation of oxidation mechanisms and the direct measurement of rate coefficients. This project will measure species time histories for mechanism diagnosis and for making direct measurements of the rate constants of key reactions in the NH3 oxidation mechanism. By using a shock tube to produce the high-temperature conditions (1000 – 2500 K), laser absorption measurements of NH2, NH3, H2O, and N2O will be performed, and the reaction rates of at least 2 important reactions will be measured with high accuracy. The successful completion of the project will advance the fundamental understanding and prediction of ammonia oxidation. By focusing on the detailed information that concentration time histories of important species can provide, many of the discrepancies that currently exist among NH3 chemical kinetics models can be resolved. Direct measurements of the rate coefficients of individual, critical reactions at combustion temperatures will further improve the accuracy of detailed kinetics mechanisms for ammonia combustion.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

由于其零碳含量和成熟的生产方法，氨 (NH3) 作为发电和推进燃料引起了人们的广泛关注，过去几年世界各地进行了许多研究，试图了解和预测其燃烧。然而，用于预测氨燃烧行为的当前模型之间存在很大差异，并且没有一个模型可以匹配整个现有数据集，因此该项目将解决当前的大部分差异。并增加可靠性首席研究员和他的团队将利用最先进的激光诊断和实验室设施来测量目前缺少的模型参数，例如氨等氢基燃料来源的研究将最终有所帮助。减少全球温室气体的产生。这个多学科研究项目将使来自机械工程和物理化学背景的研究生能够每天进行互动，PI实验室和涡轮机械实验室的本科生研究项目将扩大研究范围。参与者数量，同时让本科生接触使用激光进行燃烧化学的研究。尽管近年来在氨化学动力学方面取得了许多成果，但大多数数据都是用于表征整体反应性，即点火延迟时间和层流火焰速度然而，通过关注激波管中详细的物质时间历史的测量，可以更好地了解 NH3 的化学动力学，此类测量可以针对氧化机制的验证和速率的直接测量进行定制。该项目将测量物种时间历史，以进行机理诊断，并通过使用激波管产生高温条件（1000 – 2500 K）、激光来直接测量 NH3 氧化机理中的关键反应的速率常数。将进行 NH2、NH3、H2O 和 N2O 的吸收测量，并且将以高精度测量至少 2 个重要反应的反应速率，该项目的成功完成将促进对基础知识的了解。通过关注重要物质的浓度时间历史可以提供的详细信息，可以解决当前 NH3 化学动力学模型中单个关键反应速率系数的直接测量。燃烧温度将进一步提高氨燃烧详细动力学机制的准确性。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。